1. Field of the Invention
The present invention relates to an information recording technique for an information recording medium, and specially relates to copy control in recording contents.
2. Description of Related Art
Recently, a technique of recording various contents transmitted through a communication path, such as images and music, on an information recording medium, such as a DVD-R (DVD-Recordable) and a DVD-RW (DVD-Re-recordable), is spread. The contents are originally subjected to protection by a copyright. Illegally copying and distributing the information recording medium on which the contents are recorded infringe on the copyright. Therefore, various methods of inhibiting the illegal copy are necessary in order to effectively protect the copyright of the contents.
In order to prevent the illegal copy of the contents, there is known a copy protection system of preventing the illegal copy at the time of recording and transmitting the contents, by adding copy control information to the contents, e.g., by embedding it to a digital signal as an electronic watermark, or by encrypting the contents. A reproducing apparatus and a recording apparatus which are in conformity with the copy protection system can discriminate such copy control information, and can recognize permission or inhibition of copying the contents and a number of times of the copying.
There is known a method of protecting the copyright as follows. When an information signal corresponding to the contents is inputted to a predetermined apparatus, attribute information indicating an attribute of the apparatus is added to the inputted information signal. At the time of recording the information signal, the recording is controlled on the basis of the attribute information and the above-mentioned copy control information. Thereby, the illegal copy of the contents can effectively be prevented. This method is disclosed in Japanese Patent Application Laid-open under No. 2001-351319.
The above-mentioned method is effective when the contents are given and received as the digital signal. However, there sometimes occurs a problem that the illegal copy of the contents by using an illegal apparatus cannot be sufficiently eliminated, after the contents pass through an analog path.